Without color; lacking characteristics which give variety. blank (Adjective). Free from writing, printing, or marks; having an empty space to be filled in; as, blank paper; a blank check; a blank ballot. blank (Adjective). Without expression.
Yes they do damage hair. Every time I have tried one ,I wound up looking like a Q-tip or my head looked like cotton. A perm will damage even more and look worse if you have been coloring your hair. There's chance of it looking okay if you don't color your hair.
1 You can use them either when your hair is damp or dry, but I feel like you get better results when your hair is a bit damp. After putting the product in your hair starting from the ends, twist and scrunch your hair to get nice curls.  Repair the damage from the perm! You can save your hair maybe up to 75% in my opinion.